Separator



May 17, 1938. G. w. HAMMAck SEPARATOR Filed Jan. 11, 1937 3 Sheets-Sheet 3 FIG. 3'

fiery: IV lM/E/W'M M r/M A r roe/v5) Patented May 17, 1938 UNITED STATES PATENT OFFICE 3 Claims.

My invention relates to pneumatic conveyors and separators: particularly to those in which leaf tobacco or similar material is carried on a current of air to a separator in which the material is temporarily held while the current of air carries oil from it dust and sand and other waste, and from which the cleaned material is discharged for further processing.

The tobacco or other material is carried by a current of air into a revolving wheel which is enclosed in a drum shaped casing. The wheel is divided into two or more parts by radial planes.

The air current is caused by a difference in pressure; the lower pressure; being created in the casing by the action of a vacuum pump or exhaust fan connected to the casing, and preferably above the horizontal diameter of the casing. The revolving wheel is divided by the radial planes into compartments, open on both sides and at the periphery. These planes are extended of the casing on allsides, so that each compartment is separated from the others.

In rotary and other machines of this class it has been found that the flexible wings or edges attached to vanes, or to valves, or to other moving parts, to prevent the leakage of air around them will at length lose some of their flexibility and will take a set. The result is air leakage; and the flexible edge has to be renewed or to be reversed in its holder, either of which means a lot of work and expense. I provide against this in some measure by using a tough, resilient material, commonly used for belting and for conveyors. But even this material will take some set after awhile; and this I counteract by reversing the rotation of the pocket wheel within the machine. For this reason I build the machine symmetrically about the central vertical plane, and I arrange the drive so that the pocket-wheel may be rotated in either direction. This symmetrical design brings the inlet to the top and the outlet to the bottom of the casing. This also has the advantage of making the path of the tobacco to be cleaned but a semicircle, and a downward path all the way; so that there is very little chance of tobacco being caught between vanes and casing.

That side of each compartment which is on the outlet side of the casing is fitted with a wire screen having a mesh of suitable size for holding the material in the compartment while the small trash and dust are allowed to pass through it. As the wheel revolves each compartment is successively cut off from the air current; and its contents are delivered to a receptacle or to a conuntil they make rubbing contact with the shell veyor from which the cleaned material may be taken for further processing.

Referring to the drawings: Figure l is a vertical section in the plane of the shaft; Figure 2 is a front elevation; Figure 3 shows one of the radial planes which divide the wheel into compartments; Figure 4 is-a detail showing the man-- ner in which certain parts are fitted together; Figure 5 is a partial view, in plan, of the screen.

In Figures 1 and 2 the numeral I indicates the open end of the pipe 2 leading to the inlet 4 by which the current of air carries the material to be cleaned into the casing I2. 7 1

The air current passes out of the casing through the outlet I9. The casing I2 is of metalor of wood or of other suitable material, in shape cylindrical, like a drum, and with parallel ends I3 and 30. V v

At the center of the casing 12 the shaft 6 is mounted on bearings I. To this shaft are attached the radial planes, or vanes, 20. These vanes are preferably built up of steel framework, consisting of the members I5, and the radial members 22 and 24. The joints are made by riveting or by welding. The rectangular panel or vane bounded by the framework I5, .22, 24, and the shaft 6 is closed by a sheet of metal or other suitable material 20. The vane formed by this framework I5, 22, 24, with the panel 20, is.

firmly fixed to the shaft Ii, so that it revolves with the shaft. The outer edges of the vanes are attached to the peripheral rings I6, I6, which form a double rim to the wheel.

To the pieces I5, 22, and 24 there is attached, by bolting or riveting, a piece of material 2-I, the outer edge of which is allowed to come into rubbing contact with the shell I2. I prefer to use for this purpose a material known as fabrica; which is a tough, flexible, closely woven material. But any other suitable material may be used. Since this fin of fabrica fills the whole open space between the frame of the vane and the walls of the casing, each compartment or pocket of the wheel is sealed so far as the passage of air from one pocket to another is concerned.

As the wheel revolves each pocket will be successively presented to the casing inlet 4 and the exhaust outlet l9. After passing these two openings each pocket will be successively presented to the outlet I0, through which outlet the good material is dropped from the wheel. Refer to Figures 1 and 2. Let the wheel be revolving clockwise. The pocket 40 is about to be removed from the pull of the exhaust at outlet I9; whereas pocket 4| is coming under the influence of that pull. Pockets 42 and 43 are cut off from that influence by the vanes 25 and 26, by the radial fin 2|, and also by the annular fin [8 to which reference will now be made. Referring to Figure 1, it is obvious'that means must be provided to prevent the exhaust from pulling the material out of the pocket which is registering with'the exhaust outlet l9. Means is provided by the screen 23, which fills the circular sector formed between two adjacent vanes of the wheel and the connecting circular arc. But instead of cutting four circular sectors, one to fit each of the pockets, I make the screen 23 in the form of a disc, having a diameter equal to that of the wheel, and I secure it between the panel frame member 22 and the wheel ring I 6; see Fig. 3. To prevent material from being pulled over the edge of the screen, the annular space between the edge of the screen 23 and the shell l2 of the casing is closed by the fin I8, which is secured to the screen and revolves with it; its outer' edge sliding in an annular channel 26 formed in the flanged joint of the casing by the spacing ring 3|. See Figure 4 for this detail. This fin l8 can be made of any suitable material, of metal or of fabric.

radial fins 2| is suitable for the fin l8.

As shown in Figure 4, the casing is formed of two sections having peripheral flanges in opposed relation with respect to each other. The annular spacing ring 3| is of less width than the flanges, and is secured between them flush with the peripheral edges thereof, thereby providing the an nular space 26 between the innermost portions of the flanges, such space constituting a groove in the peripheral wall of the casing.

In Figures 1 and 2, 29 is an access door, fitted on the front of the casing opposite to the exhaust outlet l9. This door may be of metal or other suitable material. I prefer to make it of glass;

and it then forms a useful observation door as well as an access door. In the drawings it is shown as made of metal. At 28 is shown an electric lamp bulb.

I claim: 7

1. A cylindrical casing formed with an annular groove around its circular wall, and having circular ends; a shaft journaled at the ends of the casing; means for rotating the shaft; vanes spaced radially about and secured to the shaft; a circular perforated screen at one end of the vanes and mounted on the shaft in the plane of the annular groove in the shell of the casing; resilient fins attached to the edges of the vanes and projecting radially and axially therefrom,

I have found that the same fabrica which I prefer to use for the:

the edges of said fins extending to and having a continuous rubbing contact with the end walls and circular wall of the casing; an annular resilient fin secured to the edge of the circular perforated screen, the outer portion of the said annular fin entering and lying within the annular groove in the casing wall; a Vertical pipe set in the casing wall above the shaft for the admission of material to the pockets formed by the vanes and their fins to one side of the circular screen; on the same side of the screen a discharge opening at the bottom of the casing; and on the other side of the circular screen an air exhaust port in the end of the casing and remote from the bottom of the casing.

2. In a tobacco cleaning device, a cylindrical casing formed of two sections having peripheral flanges in opposed relation with respect to each other; an annular spacing ring secured between the flanges, said ring being of less width than the flanges, and disposed flush with the peripheries thereof to provide an annular space between the innermost portions of the flanges; a rotatable shaft journaled in the end walls of the casing; radially extending vanes mounted on the shaft, and having resilient edge portions in rubbing contact with the end walls and peripheral wall of the casing; a circular screen disposed concentrically of the shaft, and intermediate the end walls of the casing; and an annular fin secured to the screen and having an edge portion disposed within said annular space between the casing section flanges; said casing having a material inlet and outlet at one side of said screen, and further having an air outlet at the other side of the screen.

' 3. In a tobacco cleaning device, a cylindrical casing, a rotatable shaft journaled in the end walls. of the casing; a plurality of spaced; rectangular rigid frames secured to the shaft and extending radially of the casing; a panel carried by and extending across each of the said frames; a circular screen mounted concentrically on the shaft and secured to said frames; a resilient annular fin secured to the screen and projecting from the periphery thereof into sealing relation with the peripheral wall of the casing; and resilient fins secured to said frames and extending radially and axially therefrom into rubbing contact with the end walls and the peripheral wall of the casing; said casing having a material inlet and an outlet at one side of said screen, and further having an air outlet at the other side of said screen.

GEORGE W. HAMMACK. 

